But US official from the Commission claim the spill started at least two weeks earlier polluting 20 miles of coastline.

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California Imperial Beach Mayor Serge Dedina said Mexico had sent a "tsunami of sewage spills”

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Us-Mexico tensions have escalated after Donald Trump vowed to build a border wall

Contact with raw sewage can cause serious infections and illnesses such as diarrhoea.

US Representatives Juan Vargas and Scott Peters, who represent the San Diego area, have written to the US Secretary of State and the director of the Environmental Protection Agency calling for federal actions to prevent another incident.

Tijuana authorities say they could declare a state of emergency in order to repair the sewage system.

The row comes amid heightened tensions between Mexico and the US with President Donald Trump vowing to build a border wall.